Senate Majority Leader Harry Reid's office swiped back Wednesday at the Republican National Committee after it filed an ethics complaint over the Nevada Democrat's use of his website and Twitter account to attack the billionaire Koch brothers.

Adam Jentleson, a spokesman for Reid, dismissed the complaint as "meritless."

"Republicans' blind obedience to the shadowy billionaire Koch brothers is on full display today," Jentleson said in an email. "Nothing says 'Republicans are the party of the top one percent' like lashing out with meritless complaints as a screen to defend the Koch brothers as they rig the system to benefit billionaires like themselves. Senator Reid will continue to do everything in his power to hold the Koch brothers and their Republican enablers accountable for trying to tilt the playing field in favor of the wealthy and against the middle class."

Appearing Wednesday morning on Fox News, RNC Chairman Reince Priebus called Reid "so dirty and so unethical" for using taxpayer-funded online media to repeatedly attack the oil tycoons, who are spending millions of dollars to defeat Democratic senators in the November elections.